Operating device for an electric device and electric device with such an operating device

Abstract

An operating device for an electrical appliance comprises a flat, translucent control panel with a front and back, an operating area on the control panel in which capacitive touch sensors are arranged. These sensors detect when a finger touches the front of the control panel at a specific point within the operating area. The control panel also includes at least one indicator light below the touch sensors to display a symbol or a possible operating command that is activated or selected by touching the front of the control panel with a finger. The touch sensors can operate on the principle of capacitive crosstalk or as capacitive touch sensors, arranged in a grid on the back of the control panel within the operating area.

Description

Application area and state of the art

[0001] The invention relates to an operating device for an electrical appliance and to an electrical appliance provided with such an operating device, wherein the operating device is arranged with an operating panel on the outside of the electrical appliance.

[0002] From EP 1 158 838 A1, a control device for a cooktop is known, which has a flat control panel to detect when a finger touches the front of the control panel at a specific point. For this purpose, capacitive sensors are arranged in the four corners of a rectangular area of ​​the control panel. By determining the distance from the point where a finger touches the control panel to each of the four sensors, the location of this point can be determined. A corresponding operating function, indicated by a symbol or the like, can then be triggered.

[0003] Another control device for a cooktop is known from EP 2 395 813 A1. Capacitive touch sensors are known from EP 0 859 467 A1. Task and solution

[0004] The invention is based on the objective of creating an operating device for an electrical appliance as mentioned above, as well as an electrical appliance equipped with such an operating device, with which problems of the prior art can be avoided and in particular it is possible to design the operating device to be simple and versatile and to make it operationally reliable.

[0005] This problem is solved by an operating device with the features of claim 1 and by an electrical device equipped with such an operating device and having the features of claim 13. Advantageous and preferred embodiments of the invention are the subject of further claims and are explained in more detail below. Some of the features are described only for the operating device or only for the electrical device. However, they should be able to apply independently and autonomously to both such an operating device and such an electrical device. The wording of the claims is incorporated into the description by express reference.

[0006] The operating device features a flat control panel with a front and a back. A finger is placed on the front panel. Advantageously, the control panel can be rectangular, but this is not mandatory. It is at least partially translucent, allowing symbols or images to be displayed by backlighting. A control area is provided on the control panel, in which touch sensors are arranged. These touch sensors are designed to detect touch on the front of the control panel within the aforementioned control area, i.e., where a finger has been placed at a specific point. Advantageously, the touch sensors are capacitive, which will be explained in more detail below. Furthermore, the operating device features at least one indicator light located in the control area below the touch sensors.It is located below or behind the control panel. It serves to display a symbol, a possible operating command, or information. These can then be activated or selected by touching the front of the control panel at that location with a finger, as is typical for such control devices or touchscreens.

[0007] According to the invention, the aforementioned touch sensors are designed to be capacitive touch sensors, preferably operating on the principle of capacitive crosstalk or as capacitive touch sensors. The control panel therefore does not need to be mechanically pressed in or deformed, etc. Furthermore, the touch sensors are arranged in a grid on the back of the control panel or behind the control panel in the aforementioned operating area, for example, in a regular grid pattern similar to grid lines or the like. Alternatively, they can be designed as interlocking or overlapping elongated strips, for example, similar to the tongues of a backgammon set.

[0008] By placing touch sensors not only in the corners of the operating area of ​​the control device, as described in the aforementioned prior art, a more precise detection of finger contact is possible. This helps to better prevent operating errors and, in some cases, allows for the closer proximity of different touch points for different functions, since finger contact is detected more accurately than if sensors were placed in the corners of the operating area. Furthermore, the touch sensors can be arranged not necessarily in a regular grid or be evenly distributed, but rather in different areas where more precise differentiation is desired, where more touch sensors can be used.The use of capacitive touch sensors has the major advantage that a relatively large operating area can be covered or monitored, which is why they are preferred over optical touch sensors.

[0009] In an embodiment of the invention, the touch sensors can be formed on a flat substrate, in particular as a coating, conductor tracks, or the like. This allows for easy manufacturing, especially automated production, and eliminates the need for individual components, such as those described in EP 0 859 467 A1, which require complex individual placement during manufacturing. Furthermore, the touch sensors or conductor tracks can be transparent, enabling them to be positioned within the operating area without causing interference, particularly without obstructing the indicator light. In some cases, the touch sensors or conductor tracks can even be rendered invisible.

[0010] In a first embodiment of the invention, the conductor tracks can be divided into two groups, with the conductor tracks within each group running parallel to each other. All conductor tracks in a group thus run in the same manner and parallel, advantageously with a constant width in the operating area, and are also identical within each group. The conductor tracks can preferably also be equidistant from each other within their group. The two groups of conductor tracks can advantageously run at an angle between 60° and 120° to each other, particularly at an angle between 85° and 95°. It is especially advantageous for the conductor tracks of the two groups to intersect at a right angle, so that an overall diamond pattern is formed by the conductor tracks, preferably as a regular diamond pattern.

[0011] In an embodiment of the invention, the conductor tracks of a group can have a distance between them of between 0.1 mm and 20 mm, in particular between 0.8 mm or 3 mm and 15 mm, preferably between 1 mm and 6 mm. This allows a sufficiently large operating area to be covered, for example with an area between 25 cm² and 150 cm², without requiring an excessive number of conductor tracks or touch sensors.

[0012] In a second embodiment of the invention, the conductor tracks or touch sensors can be elongated and run close together, with the touch sensors being arranged in two groups. These groups run alternately parallel to each other in opposite directions, thus interlocking or interlocking like fingers. The touch sensors of the two groups alternate or are arranged alternately adjacent to each other. The touch sensors are elongated and each extends from or projects from a conductor track. Each conductor track thus forms an electrical connection to a touch sensor. Advantageously, the touch sensors are designed as elongated, tapered triangles that interlock alternately. Their distance from each other can be very small, for example, between 0.1 mm and 2 mm.He only needs to ensure their electrical insulation from each other. Such touch sensors then operate as individual, independent capacitive touch sensors, as described, for example, in EP 0 859 467 A1. By comparing the signal strengths at several adjacent touch sensors, the precise location of a finger touch on the control panel can be determined. Advantageously, the touch sensors do not have a constant width in the operating area; instead, their width should increase or decrease strictly monotonically, which is easily achieved, for example, by the aforementioned triangular configuration. This allows the location of a finger touch on the control panel to be determined along the length of the touch sensor.

[0013] In one embodiment of the invention, the carrier has a connection area in which the conductor tracks are routed to their electrical connection. They can be routed to connection fields on one or both sides of the carrier, with conductor tracks always remaining on the same side of the carrier. The connection fields can be exposed and / or located at an edge of the carrier or the connection area, making them easily accessible. Advantageously, the connection area is formed integrally with the carrier, simplifying manufacturing. This also allows for very efficient routing of the conductor tracks from the carrier to the connection area.

[0014] In a further embodiment of the invention, the connection area is formed in a region of the support that projects away from the support. The connection area can be rectangular and project from the rest of the support as a rectangle. The support itself can also have a rectangular shape.

[0015] In one embodiment of the invention, the support can have a thickness of less than 1 mm, preferably a thickness between 0.05 mm and 0.2 mm. It can be designed as a type of strong but flexible film made of suitable plastic, or alternatively, glass.

[0016] In an embodiment of the invention, the carrier can have an opaque coating made of a material that can be removed by laser irradiation. Such a coating can be provided on the upper surface of the carrier, facing the control panel. This allows the illuminated indicators to be displayed particularly well by means of a kind of mask. In a further embodiment of the invention, the coating can be removed to allow illumination with light sources such as LEDs, in order to display desired symbols, advantageously by backlighting.

[0017] In an embodiment of the invention, a spacer extending over a flat area can be arranged below the support, preferably corresponding approximately to the extent of the support and / or a component carrier arranged below the spacer and comprising light sources, advantageously LEDs. The spacer can have continuous light channels below which or in which the light sources are arranged. The light channels can have at least a partially uniform shape corresponding to that of the aforementioned mask with its opaque coating. In addition to the light sources, the component carrier can also include electronic components such as microcontrollers or the like, on which touch can be evaluated to control the operating device.

[0018] In one embodiment of the invention, the carrier can have an adhesive layer on its underside for adhering to a component arranged underneath, in particular to the aforementioned spacer. The adhesive layer can be covered with a release film, which is removed for assembly.

[0019] An electrical appliance according to the invention comprises the aforementioned operating device, wherein its control panel is inserted into an outer surface of the electrical appliance, or forms part of this outer surface, or constitutes the entire outer surface. The electrical appliance can be any type, advantageously a washing machine, an oven, a cooktop, or another household appliance.

[0020] In an embodiment of the invention, the electrical appliance is a cooktop with a cooktop surface and heating elements on or under the cooktop surface, wherein the cooktop surface forms the control panel and is made, in particular, of a translucent material such as glass-ceramic or tempered glass. In this case, the control area is formed directly on the cooktop surface, advantageously in a defined or specific area, and the carrier with the touch sensors is located on the underside of the cooktop surface.

[0021] These and other features are evident not only from the claims but also from the description and the drawings, whereby the individual features, either alone or in combination, may be implemented in one embodiment of the invention and in other fields, and may represent advantageous and individually protectable embodiments for which protection is claimed here. The division of the application into individual sections and subheadings does not limit the general validity of the statements made therein. Brief description of the drawings

[0022] An embodiment of the invention is schematically illustrated in the drawings and is explained in more detail below. The drawings show: Fig. 1 a side sectional view through an operating device according to the invention in exploded view, Fig. 2 the operating device made of Fig. 1In the assembled state, Fig. 3 shows a top view of a sensor carrier of the operating device with a plurality of horizontal and vertical conductor tracks running on it as sensors, Fig. 4 shows a top view of an alternatively designed sensor carrier of the operating device with a plurality of sensors running on it as pointed tongues, and Fig. 5 shows a top view of a cooktop according to the invention with an operating device according to the invention. Detailed description of the exemplary implementations

[0023] In the Fig. 1 Figure 11 shows an operating device 11 according to the invention with a control panel 13 in an exploded side view. This operating device 11 is shown here as a single functional unit, which in the assembled state according to Fig. 2 can be installed in a general electrical appliance as mentioned above, for example in an oven or in the hob according to. Fig. 5Alternatively, the control panel 13 can be formed by a cooktop element of the hob into which the control device 11 is integrated. This is already known from the prior art mentioned above.

[0024] The aforementioned control panel 13 of the control device 11 has a front 14 and a back 15. As the Fig. 2 As shown, a finger F can be placed in a control area 17 formed on the front 14 to operate a specific function of the electrical device in which the control device 11 is installed. The finger F forms a touch surface B on the front 14 of the control panel 13.

[0025] A mask 21 is pressed or glued below the control panel 13 or, in the assembled state, to its rear side 15. This mask 21 is generally opaque, but has translucent cutouts or openings in a specific symbolic shape, as is known from the prior art. These cutouts can either be rectangular to allow the visibility of a seven-segment display located underneath, or illuminated symbols can be displayed as indicator lights through corresponding cutouts or openings, for example according to [reference to relevant document]. Fig. 5Options for power settings or a pot symbol to indicate pot detection, etc. The mask 21 can be made of thin plastic, as is commonly known. Alternatively, it can be an opaque coating applied over the entire surface of a sensor carrier 23, with the desired symbols subsequently revealed by removing the coating. As a further option, it can also be applied with cutouts or light passages already present.

[0026] The sensor carrier 23, in turn, consists of thin plastic, such as a stable plastic film, or alternatively, thin glass. As shown in the top view of the Fig. 3 Pointing to the sensor carrier 23, it has an essentially rectangular shape. At the in Fig. 3At its upward-pointing upper edge, it transitions into a projecting connection section 24, advantageously in one piece. Several parallel vertical conductor tracks 25a to 25n are provided on the sensor carrier 23. Their spacing from each other can be in the range of a few millimeters, for example 5 mm, but possibly, depending on the desired resolution accuracy, also 8 mm or even 10 mm to 20 mm. The vertical conductor tracks 25a to 25n terminate at the lower free end shortly before a lower edge of the sensor carrier 23. At the top, they run closely side by side and with two bends upwards to the connection section 24, where they transition into strip-shaped contact terminals 28. These can optionally be electrically contacted directly by pressed contacts or by a plug-in connector.

[0027] At similar intervals, horizontal conductor tracks 26a to 26n are provided on the sensor carrier 23 in the operating area 17. These also extend upwards to the connection section 24, where they form contact terminals 28. They terminate shortly before the right edge. In the operating area 17, the conductor tracks 25 and 26 intersect, and the operating area is defined at the point of intersection.

[0028] Again Fig. 3As can be seen, the vertical conductor tracks 25 and the horizontal conductor tracks 26 intersect, but only once each, with each conductor track in one direction crossing all other conductor tracks in the opposite direction. Conductors in the same direction should not cross each other. Since the sensor carrier 23 is transparent, the conductor tracks 25 and 26 should also be transparent, for example, made of transparent tin oxide or other known materials. For the general function of the capacitive touch sensors, the individual electrically conductive conductor tracks must not touch each other at any point, or they must all be insulated from each other. Therefore, the vertical conductor tracks 25 and the horizontal conductor tracks 26 should be electrically insulated from each other and should not form short circuits.This can be achieved by intermediate insulating layers, or by having them run in two different layers or by passing under the other conductor track at the intersection points. Alternatively, for example, the vertical conductor tracks 25 can be applied to a top side of the sensor carrier 23 and the horizontal conductor tracks 26 to a bottom side of the sensor carrier 23. In one embodiment, the conductor tracks are made somewhat flatter at the intersection points, for example in a diamond shape corresponding to the longitudinal direction of the respective conductor track.

[0029] The dashed line is shown in the Fig. 3 a contact surface B, which according to the representation of the Fig. 2 is formed by the finger F being placed on the front surface 14 of the control panel 13. A corresponding indicator light 19 may be provided here. From the Fig. 3It can be seen that the contact area B is relatively close to the intersection point of the vertical conductor track 25c and the horizontal conductor track 26c, or is closer to these two conductor tracks than to their respective adjacent ones. Thus, either the capacitive crosstalk between conductor tracks 25c and 26c is greatest here, which a control device of the operating device 11 or the electrical device equipped with it can detect. Alternatively, it can be determined that a capacitive signal is greatest at the vertical conductor track 25c and at the horizontal conductor track 26c, or is significantly greater in each case than at the respective adjacent conductor tracks. In this case, it is not the capacitive crosstalk that is evaluated, but rather the signal strength of a capacitive signal. However, this is known in the prior art.In any case, conductor tracks 25 and 26 form capacitively operating touch sensors, either by working together with the evaluation of a capacitive crosstalk, or as capacitive sensors, i.e., each on its own.

[0030] Below the sensor carrier 23, a spacer 32, as mentioned above, is provided, for example, made of opaque plastic. For this design, reference is made to the design of German patent application DE 10 2024 120 882.1 of the same applicant, filed on July 23, 2024. The spacer 32 contains several continuous light channels 33, advantageously designed as simple cutouts or openings. The light channels 33 are shown as dotted lines.

[0031] Below the spacer 32 is a circuit board 35 with an LED 37 on its upper surface. The spacer 32 rests on top of the circuit board 35, so that the LED 37 protrudes into the light channels 33 and shines upwards to create the illuminated indicators 19 visible from above.

[0032] The advantage of the design of the sensor carrier 23 with the vertical conductor tracks 25 and the horizontal conductor tracks 26, compared to discretely designed capacitive sensors with sensor bodies, such as those known from EP 0 859 467 A1, DE 10 2015 214 008 A1, or DE 10 2016 206 174 A1, lies primarily in the reduced complexity. The conductor tracks 25 and 26 can be applied to the sensor carrier 23 relatively easily and in large numbers using coating processes. The spacer 32 is a single component that can be mounted quickly and easily. Similarly, simple and high-luminosity LEDs 37 can be used.

[0033] Furthermore, variants of the operating device 11 can be manufactured relatively easily by designing the mask 21 so that it can be laser-cut to create different cutouts. Alternatively, an opaque, removable layer of the mask 21 can also be provided on one side of the sensor carrier 23, advantageously on the top side. The sensor carrier 23, in turn, can be easily bonded to the spacer 32 by means of an adhesive side 29 on the underside to form a single assembly, which can then be relatively easily attached to the circuit board 35.

[0034] If such a control device 11 is integrated into a hob, the control panel 13 is formed by the hob plate or the mask 21 is pressed with its upper side against an underside of the hob plate, advantageously pressed with spring force.

[0035] In the Fig. 4A differently designed sensor carrier 123 is shown, which is also essentially rectangular and has an upwardly projecting connection section 124. The sensor carrier is coated with elongated, narrow, triangular conductor tracks, which may optionally be transparent and made of a suitable material. Conductor tracks 125a to 125n project downwards from top to bottom. Conductor tracks 126a to 126n project upwards, advantageously the same number as conductor tracks 125. These conductor tracks 125 and 126 do not touch each other, not even on their way to the connection section 124, where they in turn transition into contact terminals 128.

[0036] In this configuration of the capacitive sensors 125 and 126, no capacitive crosstalk is detected via a contact surface B above them; instead, the signals of adjacent sensors or conductor tracks 125 and 126 are compared with each other. Here, the contact surface B is clearly located above the two conductor tracks 125b and 125c, as well as above conductor track 126b. By comparing the signal strength at all three of the aforementioned covered conductor tracks, the precise location of the contact surface B within the operating area 17 can be determined.

[0037] In Fig. 5 A cooktop 1 according to the invention is shown as an electrical appliance, comprising a cooktop plate 2 and four heating elements 3a to 3d. A control device 11 according to the invention, shown here with dashed lines, is arranged at the bottom center. The continuous cooktop plate 2 forms the control panel, on which a finger F can be placed.

[0038] The operating device 11 has an operating area 17 in which several indicator lights 19 are provided, a seven-segment display on the right and in the middle possibilities for adjusting the power of one of the heating devices 3a to 3d.

Claims

1. Control device for an electrical appliance, wherein the control device comprises: - a flat control panel with a front and back, wherein the control panel is at least partially transparent, - a control area on the control panel in which touch sensors are arranged that detect touching the front of the control panel in the control area by means of a finger at a specific point, - at least one indicator light in the control area below the touch sensors for displaying a symbol or possible operating command that is activated or selected by touching the front of the control panel with a finger characterized by the fact that - the touch sensors are capacitive touch sensors, preferably designed according to the principle of capacitive crosstalk or operating as a capacitive touch sensor, - the touch sensors are arranged in a grid on the back of the control panel in the operating area.

2. Operating device according to claim 1, characterized by the fact that the touch sensors are formed on a flat substrate, in particular as a coating or as conductor tracks.

3. Operating device according to claim 2, characterized by the fact that The coating or conductor tracks are divided into two groups, and the coating or conductor tracks within each group run parallel to each other, with the two groups of coating or conductor tracks running at an angle between 60° and 120° to each other, in particular between 85° and 95° to each other.

4. Operating device according to claim 2, characterized by the fact thatthe touch sensors are elongated and run close together, in particular the touch sensors are formed in two groups and run alternately parallel to each other in opposite directions, being elongated starting from conductor tracks, preferably as elongated and tapered triangles.

5. Operating device according to one of claims 2 to 4, characterized by the fact that the carrier has a connection area in which the conductor tracks are led to the electrical connection, in particular to connection fields on one side of the carrier, wherein the connection fields are exposed and / or are arranged at an edge area of ​​the carrier.

6. Operating device according to claim 5, characterized by the fact that the connection area is formed in an area of ​​the support that protrudes from the support, preferably the connection area being rectangular and protruding from the rest of the support as a rectangle.

7. Operating device according to one of claims 2 to 6, characterized by the fact that The conductor tracks of one group, preferably the conductor tracks of both groups, have a distance between each other of between 0.1 mm and 20 mm, preferably between 0.8 mm and 15 mm.

8. Operating device according to one of the preceding claims, characterized by the fact that the support has a thickness of less than 1 mm, preferably a thickness between 0.05 mm and 0.2 mm.

9. Operating device according to one of the preceding claims, characterized by the fact that The carrier has an opaque coating made of a material that can be removed by irradiation with a laser, the coating preferably being provided on the top of the carrier facing the control panel.

10. Operating device according to claim 9, characterized by the fact that The coating has been removed to allow light to pass through and display symbols.

11. Operating device according to one of the preceding claims, characterized by the fact that A spacer is arranged below the support, which is extended over a surface corresponding to the extent of the support and which has continuous light channels, wherein a component support is arranged below the spacer with light sources that are arranged below or in the light channels.

12. Operating device according to claim 11, characterized by the fact that The carrier has an adhesive layer on its underside, preferably covered with a protective film, for sticking onto a part arranged underneath, in particular onto the spacer.

13. Electrical appliance with an operating device according to one of the preceding claims, characterized by the fact that the control panel is inserted into an outer surface of the electrical appliance, or is part of that outer surface, or forms the entire outer surface.

14. Electrical appliance according to claim 13, characterized by the fact thatIt is a cooktop with a cooktop plate and heating devices on the cooktop plate, wherein the cooktop plate forms the control panel and is made in particular of translucent material such as glass ceramic or tempered glass.

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